The overall goal of this project is to examine, at a molecular level, the correlation between structure and function for several neurotransmitter-gated channels, receptors, and related proteins. Currently, the main focus of the laboratory is the examination of the secondary structure, topology, and functional role of domains and specific residues of the homomeric recombinant human *1 glycine receptor overexpressed in a baculovirus expression system. This inhibitory gated anionic channel is a member of the ligand-gated superfamily, which include the homologous nicotinic acetylcholine receptor, the 5-HT3 serotonin receptor, and the GABA receptor, all of which act in rapid mediation of signal transduction at the synapse. These investigations may provide insight into the general conserved mechanism used in channel design. Analogous studies concerning the NMDA type glumatmate receptors and the gonadotropin releasing hormones (GnRH) receptor will also be conducted. These recep tors, too, are members of large families, and may their structural feature may be paradigmatic; the NMDA receptor is a member of the excitatory glutamate receptor family which act in synaptic transmission and excitotoxicity, and the GnRH receptor is a member of the large G-protein coupled receptors and is a pivotal role in regulating coordination of the neural and endocrine systems. In addition, crystalliszation trails of EP 24.15 a zinc metalloendopeptidase which degrades GnRH, are also underway.